The reinforced retaining walls of the prior art utilized various configurations of modular blocks. The components of these prior art wall utilized various shapes and sizes of modular blocks which were capable of being assembled in several different arrangements to form a crib or bin type of wall with interconnecting parts. The weight of the fill material bearing on the wall was used to keep the wall in place.
Other walls utilized special shaped blocks designed to interlock and be held in place by tension members along the centerline of the wall.
Still other retaining walls utilized other shapes of interlocking blocks having vertical holes therein which were then dropped in place using reinforcing rods passing though the holes after the reinforcing rods were first imbedded in a concrete footing.
Still other retaining walls utilized stacked and alternately staggered rows of chevron shaped or grooved blocks which were also connected to anchoring devices embedded in the backfill along one side of the wall.
In the retaining walls of the prior art the main methods of preventing overturning of the wall were to provide one or more anchors extending horizontally into the ground or soil being held back or retained by the wall, construct a crib or bin of considerable thickness or slope the face of the wall so that horizontal earth pressures were reduced. The weight of the earth was then used to counteract any overturning moment by forces acting at right angles to the wall.
One free-standing retaining wall of the prior art utilizes large concrete blocks which must be handled by barges or derricks and a rod passing down through the center of the wall. In this wall the large size of the concrete blocks is utilized to resist overturning moments.
These retaining walls of the prior art generally required excessive excavation for their installation, large machinery or special skill or strength and know-how in their construction and assembly.